No dress codes are laid down, although wearing a dominant's collar is
used as a symbol of that dominant's authority over the submissive.
Collars are also used figuratively ("worthy of a collar") to represent
the privilege of service.

A protocol for introductions is laid out, based on the status of the
participants and also conveying information in their involvement in
BDSM.

Inferiors are introduced to superiors.

Introductions are in the order of hierarchy (a submissive's
dominant is at the top of their hierarchy.)

"I would like you to meet X" indicates the interaction is
vanilla.

"I would like to introduce X to you" indicates the
interaction is scene-friendly.

"I would like to present X to you" indicates "a very
formal
scene protocol". This form shouldn't be used by submissives making
introductions.

(This idea of conveying information through the form of introduction is
rather like the Mafia-aware ("connected") and Mafia-member ("made")
protocol described in
Donnie
Brasco: 'When I introduce you, I'm gonna say, "This is a friend
of
mine." That means you're a connected guy. Now, if I said instead, "This
is a friend of ours," that would mean you're a made guy. Capiche?')